The invention relates generally to the field of motor drives and similar devices comprising a number of power electronic circuits. More particularly, the invention relates to techniques for verifying proper selection, installation, and operability of components in such devices.
A wide range of power electronic devices are known and currently available, particularly in automation context. For example, many electric motors and other loads in industrial, commercial, automation, process, transportation, and other contexts are powered by electronic circuits that control and regulate the characteristics of electrical power based upon the application and load characteristics. In a particularly important range of products, variable frequency, multi-phase output is provided for regulating the speed, torque, and other characteristics of driven motors. Motor drives used in such applications have become increasingly complex, with multiple layers of control, monitoring, drive, and power circuitry interconnected for generating the desired output signals.
A typical motor drive used for automation applications includes a converter that transforms alternating current (AC) power to direct current (DC) power that is applied to a DC bus. Power from the DC bus is then converted via an inverter to controlled frequency AC power for application to the load. The converter may be passive (non-switched) or active (switched), while the inverter circuitry typically includes sets of power electronic switches that are switched between conducting and non-conducting states to provide the desired output waveform. Such circuits are available in single and multi-phase configurations.
As load requirements and circuitry become increasingly complex, significant modularity has been developed for circuit topologies of the type described above. For example, smaller loads may be driven by a single converter coupled to a single inverter via a single DC bus. Increasingly, however, larger loads may be powered by parallel inverters or entire paralleled drives, the output signals of which are joined to provide a single, higher powered output. Inverters or converters are often manufactured in a wide range of sizes to accommodate different loads. Many components in such a family of inverters or converters will be the same for all sizes, while other components will be different depending on the specific power rating.
In all of these topologies, challenges arise at multiple stages in the life of the equipment, including manufacturing, operation, and servicing. In particular, the equipment may employ multiple separate, modular components that may be interconnected to provide the desired functionality. Such components may include control circuitry, interface circuitry, power layer circuitry, switching modules, feedback and monitoring components, and so forth. When the equipment is initially manufactured and commissioned, if erroneous components have been used, this can lead to malfunction and even failure of the overall system or of certain components of the system. Similarly, during operation, the failure of certain devices or certain signal communications can lead to disabling or failure of the system or of components. During servicing, where certain components are factory or field replaceable, or repairable, the erroneous selection or connection of such components can similarly lead to system or component failure.
There is a need in the field, therefore, for techniques that will reduce the risk or avoid the potential for improper component selection and installation, and that can monitor operation of components during their service life.